Green Box -- perfect for the non-green thumb in some of us

Had it not been for one unattractive, hot tar paper roof, Merrill Smith's bright idea -- a portable garden called the Green Box -- might never have bloomed.

Smith, an avid gardener (she was part of our story on container gardens), moved from the burbs to Lincoln Park five years ago, trading her backyard vegetable garden for access to the aforementioned tar papered rooftop. Instead of giving up her green thumb, she went about trying to figure out how to make the space work for her.

"I read about a guy building these big salad tables, about six feet long. I had a friend make one of those for me. Then I started kicking around the idea of just how I could make it more portable," Smith says.

As she tweaked the design, she pitched her idea to the nonprofit Resource Center, which operates City Farm, just down the road from the Cabrini-Green housing projects. The farm bit. "And then I became this junkyard dog," Smith says, trolling Dumpsters for lumber.

The two-by-three-foot Green Box -- Smith builds these with her own hands, people! (her 16-year-old son helps) -- is made solely of recycled or repurposed materials, including old crib slats. It comes with a burlap bag of City Farm compost, red and green lettuce seeds and directions.

It, Smith says, will not fail even the most novice gardener.

"This really is the closest thing to instant gratification in vegetable gardening," she says.

The Green Box makes its debut from 9 a.m. to noon Saturday at City Farm, 1204 N. Clybourn. Smith will be there, shoveling compost and showing people how the thing works. A box costs $75, $50 of which goes back to the farm and the Resource Center. RSVP: greenboxchicago@me.com